The Decemberists' latest inspiration

a single album-length song

by Walter Tunis

Almost by definition, pop music is viewed as an easily digestible commodity. It commands that you stick to a familiar and accessible theme, conjure an appealing melody, and for crying out loud, it’s got to move along briskly. A pop tune isn’t an epic, you know.

Or is it?

The newest album by The Decemberists, “The Hazards of Love,” harks back to an artistically haughty enterprise known as the “concept album.” That means that even though it is technically divided into 17 songs, the recording is essentially one long piece — and a fairly fanciful one at that. Its story line involves fabled but forbidden love, forest witches and the promise of some nasty deeds from a fellow known as The Rake.

So what could be more out of step with the pop mainstream than to release an album that is, in essence, a single extended work? How about going on tour and performing the entire thing from start to finish?

Did Capitol Records, which signed the onetime indie sensation in 2005, think such moves conflicted with conventional pop strategies? Hard to say. But Decemberists drummer John Moen had an initial word for releasing and performing a concept work like “The Hazards of Love”: “inadvisable.”

“I thought, ‘OK, now that everyone is back to ordering just one song at a time on the Internet, we’re going to make an entire album that is one big, long song,’” Moen said. “But you know, sometimes it can be really interesting to do something that even you are telling yourself is a bad idea.”

“The Hazards of Love” didn’t sell in Michael Jackson-like numbers upon its release last spring, but it did become the highest-charting album of the band’s career, making it to No. 14 on the Billboard Top 100. More arresting than that, though, was the sheer expression and invention of the record.

Inspired by a 1966 EP disc of the same name from British folk songstress Anne Briggs, “The Hazards of Love” moves from delicate passages of dark acoustics to thundering bits of keyboard-charged rock ‘n’ roll. It’s part Brit-folk fairy tale (which is fascinating given that the band is from Portland, Ore.) and part rock ‘n’ roll theater.

“I love The Decemberists,” said fellow Portland musician Scott McCaughey, who recruited all of The Decemberists for cameos on his new album, “Killingsworth,” with indie rockers The Minus 5. “Great lyrics, absolutely killer musicians ... They’re incredible. They go from doing really stripped-down English folk to bombastic prog-rock, but also sound great on everything in between. I really love that about them.”

“The Hazards of Love,” like all Decemberists records, is the invention of Colin Meloy. As the band’s vocalist, frontman, co-founder and chief songwriter, he mapped out the album’s epic pop design. And this wasn’t the first time that Meloy had devised a concept recording for The Decemberists (which currently include multi-instrumentalist Chris Funk, keyboardist Jenny Conlee, bassist Nate Query and Moen). In 2004, he wrote the Irish-inspired (though decidedly un-Irish-sounding) “The Tain.” But that EP’s five songs lasted a mere 18 minutes. “The Hazards of Love” runs nearly an hour.

“It was daunting, firstly,” Moen said. “I wasn’t in the band when ‘The Tain’ was recorded. So I was kind of nervous about how all of this was going to come together. But Colin made a pretty detailed map, a demo, for us. Once you listened to everything, you realized how there are songs in there that hold up on their own just as much as the other material he writes.

“So once we heard the tunes, the ideas just started popping in our brains about how to make this sound unique. It became a kind of creative puzzle.”

On tour, the band is being augmented for the new material by vocalists Shara Worden (of My Brightest Diamond) and Becky Stark (of Lavender Diamond). A second set features earlier Decemberists songs.

“I think we have proved that a show like this really isn’t such a silly thing to do,” Moen said. “I mean, I wasn’t sure at first this was such a good plan, but it’s been great to pull off playing the whole record, to get the whole thing done. I wouldn’t have predicted something like this at all. But I’m really proud to be part of it.”